Peripartum mental illness appears more common in mothers with multiple sclerosis

Key takeaways:

• Mothers with multiple sclerosis were at the highest risk for incident mental illness during the first year postpartum.
• The most common incident mental illness during the prenatal period was anxiety.

Mothers with multiple sclerosis had an elevated incidence and prevalence of peripartum mental illness vs. mothers without MS and those with or without other chronic conditions, according to study results.

The study was published in Neurology, the medical journal of the American Academy of Neurology.

“Previous studies have shown that women with MS are more likely to have depression, anxiety disorders and bipolar disorder compared to women without MS,” Ruth Ann Marrie, MD, PhD, professor of medicine at Dalhousie University in Halifax, Canada, and professor of medicine and community health sciences at the University of Manitoba in Winnipeg, Canada, said in an American Academy of Neurology press release. “Mental health struggles can affect both parents and kids, making it important to understand how mental health challenges around pregnancy affect people with MS.”

In a retrospective cohort study, Marrie and colleagues used linked population-based administrative health data from Ontario to compare the incidence and prevalence of peripartum mental illness among 894,852 mothers (mean age, 28.6 years) with and without MS, epilepsy, inflammatory bowel disease (IBD) or diabetes who had a live birth with index dates between Jan. 1, 2000, and March 31, 2017. Overall, 1,745 mothers had MS, 5,954 had epilepsy, 4,924 had IBD, 13,002 had diabetes and 869,227 had none of these conditions.

The researchers used validated case definitions to identify mental illnesses — including depression, anxiety, bipolar disorder, psychosis, substance use and suicide attempts — during the prenatal period and the 3 years postpartum.

Among mothers with MS, any incident mental illness affected 8.4% during the prenatal period and 14.2% during the first year postpartum, according to the researchers.

During the prenatal period, the most common incident conditions among mothers with MS were anxiety (3.8%), depression (0.82%) and substance use (0.54%).

The researchers observed that the first year postpartum was a higher risk period for any incident mental illness among mothers with MS compared with the prenatal period (incidence ratio [IR] = 1.27; 95% CI, 1.08-1.5).

In comparison, the group of mothers without any chronic conditions had an incidence proportion of any mental illness of 7.06% during the prenatal period, with a 2.28% incidence of anxiety and 0.95% of depression.

After multivariable adjustment, results showed that mothers with MS had an increased incidence of any mental illness during the prenatal period (IR = 1.26; 95% CI, 1.11-1.44) and first year postpartum (IR = 1.33; 95% CI, 1.2-1.47) vs. those without MS, epilepsy, IBD or diabetes. A similar trend occurred when looking at individual mental health conditions except for suicide attempts, for which the sample was too small.

During the prenatal period, compared with the other disease cohorts, mothers with MS appeared to have increased incidence of depression, anxiety, psychosis and substance use compared with those with IBD and diabetes, as well as for depression and psychosis compared with the epilepsy cohort.

In the first year postpartum, women with MS also showed higher rates of incident mental illness compared with those with diabetes (IR = 1.16; 95% CI, 1.04-1.29), epilepsy (IR = 1.05; 95% CI, 0.93-1.18) and IBD (IR = 1.03; 95% CI, 0.91-1.16).

Next, researchers looked at prevalent mental illness among mothers with MS, and they found a prevalence estimate of 42% for any mental illness during the prenatal period and 50.3% during the first year postpartum; the most prevalent specific conditions during the first year postpartum were anxiety (25.1%) and depression (4.6%). Again, the adjusted prevalence of prenatal mental illness appeared higher in this cohort compared with mothers without chronic conditions.

“These findings emphasize the need for preventive and early treatment of mental illness,” Marrie said in the release. “Future studies should look at how MS affects mental health in mothers during and after pregnancy and if it’s worse in different stages of MS. Doctors should know about these risks, make sure to check mental health and provide treatment if needed.”

In a related editorial, Lindsay A. Ross, MD, a neurologist at the Mellen Center for Multiple Sclerosis Treatment and Research at Cleveland Clinic, discussed how the study by Marrie and colleagues highlights the challenges faced by pregnant women with MS.

She also shared recommendations for clinicians caring for women with MS, such as implementing validated screening tools for peripartum mental illness and substance use or having regular discussions with patients about these topics.

Ross noted that the study had several limitations, including its reliance on administrative data and the applicability of the results outside of Canada.

“While we look forward to research on scalable implementation for screening and treatment of peripartum mental illness and substance abuse in women with MS, as the study by Marrie et al. highlights, clinicians need to acknowledge that peripartum mental illness is common in women with MS and should be accounted for as part of their routine in family planning, pregnancy and postpartum encounters,” she wrote.

References:

• Pregnancy may increase risk of mental illness in people with MS. https://www.aan.com/PressRoom/Home/PressRelease/5228. Published Jan. 22, 2025. Accessed Jan. 28, 2025.
• Ross LA, et al. Neurology. 2025;doi:10.1212/WNL.0000000000213366. Published Jan. 22, 2025. Accessed Jan. 28, 2025.